1. Field of the Invention
The present invention relates to a toner cartridge applicable to an image forming apparatus such as a copying machine, a facsimile, a printer or the like.
2. Description of Related Art
A toner cartridge having a delivering spiral and an agitating paddle in its cartridge body has been proposed. In such a kind of toner cartridge, toner contained in the cartridge body is agitated by rotating the agitating paddle, so that toner blocking can be prevented. The word xe2x80x9ctoner blockingxe2x80x9d means that toner, not agitated for a long time, sets of itself.
The toner agitated by the agitating paddle is delivered to an outlet port by the delivering spiral and then supplied to a developing device.
In the abovementioned toner cartridge, though toner in the vicinity of the agitating paddle during rotating is agitated, toner in the corners of the cartridge body and regions out of reach of the agitating paddle cannot be sufficiently agitated. Therefore, sometimes toner partly remains in the cartridge body and cannot be wholly supplied to the developing device.
A first object of the present invention is to provide a toner cartridge capable of wholly supplying toner in its cartridge body to a developing device or the like.
A second object of the invention is to provide a toner cartridge having a delivering spiral and an agitating paddle in its cartridge body so that toner in the cartridge body is agitated by the agitating paddle and the agitated toner is wholly delivered by the delivering spiral.
A third object of the present invention is to provide a toner cartridge in which toner blocking or setting in the cartridge body is prevented.
A toner cartridge according to the present invention includes a cartridge body for containing toner, an agitating paddle for agitating toner, and a toner blocking/setting prevention member operative in cooperation with the agitating paddle for preventing toner in the cartridge body from blocking or setting, the agitating paddle and the toner b locking/setting prevention member being. provided in the cartridge body.
In a toner cartridge according to an embodiment of the present invention, a delivering spiral comprises an elongated rotation shaft in the cartridge body and a spiral blade extended outward from the circumferential surface of the rotation shaft and continuously elongated in the longitudinal direction of the rotation shaft to form a spiral having a predetermined pitch; and the agitating paddle comprises an elongated rotation shaft disposed in parallel with the rotation shaft of the delivering spiral and a plurality of agitating wings protruded from the rotation shaft. The agitating wing of the agitating paddle is provided with a contacting projection which contacts with the spiral blade when the agitating paddle is rotated. The contacting projection functions as a toner blocking/setting prevention member. The contacting projection may be formed integrally with the agitating wing to constitute a part of the agitating wing. Preferably, the contacting wing has a width substantially equal to a pitch of the spiral blade.
With this structure, when a part of the agitating wing contacts with the spiral blade, the delivering spiral is oscillated to oscillate toner in the cartridge body, so that toner blocking can be prevented. Further, since the agitating wing contacts with the spiral blade only in a small width corresponding to a pitch, toner is prevented from being pressed against the spiral blade and setting. As a result, the amount of toner remaining in the cartridge body can be reduced.
The contacting projection may be provided on an arbitrary one or ones among the plurality of agitating wings.
With this structure, since only an arbitrary one or ones among the plurality of agitating wings contacts or contact with the spiral blade, the contacting range can be narrowed and thereby toner setting on the spiral blade can be further reduced. Furthermore, the manufacturing cost can be reduced in comparison with a case in which all of the agitating wings are provided with contacting projections respectively.
The abovementioned cartridge body may have a recessed section in the vicinity of one side surface thereof. In this case, the agitating paddle has two ranges in the longitudinal direction; that is, one range in which no agitating wing can be provided because of the recessed section, and the remaining range 16 in which agitating wings can be provided without interference with the recessed section. In this case, preferably, two agitating wings among the plurality of agitating wings are each provided with a contacting projection, and the two contacting projections are provided on the agitating wings within regions, each corresponding to three tenths of the whole of the range in which agitating wings can be provided, extending from each end of the range.
With this structure, the contact portions between the agitating wings and the spiral blade are limited to two potions capable of intensely oscillating the delivering spiral, so that the delivering spiral can be effectively and sufficiently oscillated.
In another embodiment of the present invention, a toner blocking/setting prevention member includes an oscillating plate, which is operated by the agitating paddle so as to assist in agitating toner. With this structure, since the oscillating plate assists in agitating toner in the cartridge body, stable toner supply can be achieved.
Where the cartridge body includes a region out of reach of the agitating effect of the agitating paddle, it is preferable to provide an oscillating plate in that region. Thereby, toner blocking can be prevented. As a result, the amount of toner remaining in the cartridge body can be reduced.
The abovementioned oscillating plate may comprise an elastic and flexible (preferably long) thin plate and be fixed in the curved state to the cartridge body at its both ends. With this structure, the oscillating plate, being in the curved state, is provided with repelling force, and therefore, its agitating effect can be increased.
Where the cartridge body has a top plate, the oscillating plate may be fixed to the top plate. With this structure, only by attaching the top plate having the oscillating plate fixed thereto, to a container section of the cartridge body, the oscillating plate can be easily disposed in the cartridge body. Accordingly, error in assembling the parts can be decreased.
The oscillating plate may be positioned in such a manner that the agitating paddle during rotating can repel the oscillating plate and the repelled oscillating plate can agitate toner. With this structure, the oscillating plate can be operated using the rotation of the agitating paddle. Therefore, with the simple structure, toner in the cartridge body can be effectively and sufficiently agitated.
The foregoing and other objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of embodiments of the present invention given with the accompanying drawings.